Metamath Proof Explorer


Theorem opeq12i

Description: Equality inference for ordered pairs. (Contributed by NM, 16-Dec-2006) (Proof shortened by Eric Schmidt, 4-Apr-2007)

Ref Expression
Hypotheses opeq1i.1 𝐴 = 𝐵
opeq12i.2 𝐶 = 𝐷
Assertion opeq12i 𝐴 , 𝐶 ⟩ = ⟨ 𝐵 , 𝐷

Proof

Step Hyp Ref Expression
1 opeq1i.1 𝐴 = 𝐵
2 opeq12i.2 𝐶 = 𝐷
3 opeq12 ( ( 𝐴 = 𝐵𝐶 = 𝐷 ) → ⟨ 𝐴 , 𝐶 ⟩ = ⟨ 𝐵 , 𝐷 ⟩ )
4 1 2 3 mp2an 𝐴 , 𝐶 ⟩ = ⟨ 𝐵 , 𝐷